Article
Physics, Nuclear
Son T. Nguyen, Matthias R. Schindler, Roxanne P. Springer, Jared Vanasse
Summary: The study extends the analysis of two-body hadronic parity violation from operators with one derivative to operators with three derivatives, within the framework of a pionless effective field theory and large-Nc expansion. The relationships among EFT LECs emerge in the large-Nc expansion, and the renormalization group scale dependence of these LECs is discussed. This analysis can complement lattice QCD calculations and help prioritize future parity-violating experiments.
Article
Astronomy & Astrophysics
Ruben Flores-Mendieta, Carlos Isaac Garcia, Johann Hernandez, Maria Anabel Trejo
Summary: This study examines baryon magnetic moments in baryon chiral perturbation theory in the large-Nc limit, comparing different correction terms and operator structures. Numerical evaluations and parameter fits show the importance of considering nondegenerate intermediate baryons for a consistent determination of free parameters in the analysis.
Article
Physics, Nuclear
Yonggoo Heo, C. Kobdaj, Matthias F. M. Lutz
Summary: This paper reconsiders the chiral Lagrangian with three-flavor baryon fields and analyzes the low-energy constants (LEC) that contribute to the axial-vector and pseudoscalar currents. The number of relevant LEC at subleading order is 23. The results are illustrated by analyzing the axial-vector coupling constants and strong decay widths of the baryon decuplet states.
EUROPEAN PHYSICAL JOURNAL A
(2023)
Article
Physics, Nuclear
M. Kohno, H. Kamada, K. Miyagawa
Summary: This article presents an expression of partial-wave expansion for three-baryon interactions in chiral effective field theory, which is more general compared to previous methods. By utilizing this derived formula, the folding potential of a ?-deuteron is evaluated, providing valuable information for future studies on ?NN three-baryon forces and their contribution to hypertritons through sophisticated Faddeev calculations. The microscopic understanding of ?NN three-baryon forces, along with two-body ?N interactions, is crucial for the description of hypernuclei and neutron-star matter.
Article
Multidisciplinary Sciences
B. Behzadmoghaddam, M. Radin, S. Bayegan
Summary: In this paper, the chiral effective field theory is used to study the spin singlet channel S-1(0) of proton-proton scattering, adopting a new suggested power counting. The pp zero scattering amplitude is reproduced by including one pion exchange at leading order (LO) and the Coulomb interaction between protons at next-to-leading order (NLO). This provides a systematic improvement up to NLO compared to the result obtained from the Nijm93 potential model.
SCIENTIFIC REPORTS
(2023)
Article
Physics, Nuclear
Rui Peng, Songlin Lyu, Sebastian Konig, Bingwei Long
Summary: A momentum-dependent formulation based on a stationary spin-0 and isospin-1 dibaryon field is proposed to improve convergence of chiral effective field theory in the S-1(0) channel of NN scattering. Rapid order-by-order convergence is found in S-1(0). The study also investigates the triton binding energy and compares it to standard chiral effective field theory with partly perturbative pions, while examining the consistency of the chiral Lagrangian for the new formulation.
Review
Physics, Nuclear
Thomas R. Richardson, Matthias R. Schindler, Roxanne P. Springer
Summary: This paper presents a method for ordering two-nucleon interactions based on their scaling with the number of QCD colors. It discusses the application of this method to two- and three-nucleon interactions, as well as weak and BSM interactions, and raises some open questions in the field.
ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE
(2023)
Article
Astronomy & Astrophysics
Peng-Cheng Qiu, De-Liang Yao
Summary: The chiral effective meson-baryon Lagrangian for interactions between doubly charmed baryons and Goldstone bosons is constructed up to q(4) order. A total of 8, 32, and 218 linearly independent invariant monomials of O(q(2)), O(q(3)), and O(q(4)) are considered. This Lagrangian allows for studying the chiral dynamics and relevant phenomenology of doubly charmed baryons at complete one-loop level, and also includes a discussion on the nonrelativistic reduction of the Lagrangian for completeness.
Article
Astronomy & Astrophysics
Ruben Flores-Mendieta, Carlos Isaac Garcia, Johann Hernandez
Summary: This study computes the baryon axial vector current in heavy baryon chiral perturbation theory in the large-Nc limit, including one-loop nonanalytic corrections and contributions from both intermediate octet and decuplet baryon states. The theoretical expressions are obtained under the condition of vanishing decuplet-octet mass difference, allowing a full comparison with conventional results for three flavors of light quarks. The predictions of the formalism agree well with experimental data, as confirmed through a numerical analysis and extraction of free parameters.
Article
Astronomy & Astrophysics
P. Bickert, S. Scherer
Summary: In this study, we calculated the eta((')) -> pi(+)pi(-)gamma decay process at the one-loop level in large-N-c chiral perturbation theory, up to and including next-to-next-to-leading order (NNLO). The numerical evaluation of the results was performed at LO, NLO, and NNLO, with relevant low-energy constants fitted to experimental data. We discussed the widths and decay spectra of eta((')) -> pi(+)pi(-)gamma, as well as eta((')) -> pi(+)pi(-)l(+)l(-) with l = e, mu.
Article
Astronomy & Astrophysics
P. M. Copeland, Chueng-Ryong Ji, W. Melnitchouk
Summary: The study computes the self-energies of flavor SU(3) octet and decuplet baryons within a relativistic chiral effective theory framework, deriving the leading nonanalytic chiral behavior for the masses. A finite-range regularization consistent with Lorentz and gauge invariance is applied, and the relative importance of various meson-baryon loop contributions to the self-energies is numerically studied. A comparison is made between relativistic results and earlier approximations within the heavy baryon limit.
Review
Physics, Multidisciplinary
Robert B. Baker, Matthew Burrows, Charlotte Elster, Kristina D. Launey, Pieter Maris, Gabriela Popa, Stephen P. Weppner
Summary: The effective interaction between a nucleon and a nucleus is crucial for reaction theories. Recently, the calculation of the leading order term in the Watson multiple scattering approach has been achieved ab initio, allowing for systematic exploration of uncertainties in nucleon-nucleus elastic scattering observables. This study focuses on the calculation of the leading order nucleon-nucleus interaction using a specific chiral NN interaction and light nuclei with a 0(+) ground state, and analyzes elastic scattering observables for He-4, C-12, and O-16 projectiles with energies between 65 and 200 MeV.
FRONTIERS IN PHYSICS
(2023)
Article
Physics, Nuclear
Thomas R. Richardson, Xincheng Lin, Son T. Nguyen
Summary: Recent proposals for the use of light nuclei as dark-matter direct detection targets require a strong theoretical understanding of nuclear physics. Calculations for dark-matter-light-nucleus scattering are performed using pionless effective field theory and large-N-c expansion. Constraints for the relative sizes of dark-matter couplings to different nucleon currents are obtained through the large-N-c expansion, and used to predict the relative sizes of spin-dependent and spin-independent cross sections for dark-matter scattering off various light nuclei.
Article
Physics, Nuclear
Takayuki Miyagi
Summary: The applicability of nuclear ab initio calculations has expanded rapidly in the past decades, but starting research projects in this field remains challenging due to required numerical expertise. To address this issue, this paper introduces the numerical code NuHamil for generating nucleon-nucleon (NN) and three-nucleon (3N) matrix elements in a spherical harmonic-oscillator basis. Ground-state energies of selected doubly closed shell nuclei are calculated using the no-core shell-model (NCSM) and in-medium similarity renormalization group (IMSRG). The code is written in modern Fortran and supports OpenMP+MPI hybrid parallelization for 3N matrix-element calculations.
EUROPEAN PHYSICAL JOURNAL A
(2023)
Article
Physics, Nuclear
S. K. Saha, D. R. Entem, R. Machleidt, Y. Nosyk
Summary: We present local, position-space chiral NN potentials through four orders of chiral effective field theory. Our potentials accurately reproduce the NN data below 190 MeV and show substantial agreement with the phenomenological AV18 potential in the intermediate range. These potentials provide a solid basis for systematic ab initio calculations of nuclear structure and reactions, and may help solve outstanding problems in microscopic nuclear structure.
Article
Physics, Multidisciplinary
E. Epelbaum, J. Gegelia, N. Lange, U-G Meissner, M. Polyakov
Summary: The matrix element of a local operator between hadronic states is used to define the associated spatial density. The charge density of a spinless particle is studied as an example, clarifying its relationship to the electric form factor. The results provide an unconventional interpretation of the spatial densities of local operators and their moments.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Particles & Fields
H. Alharazin, B. -d. Sun, E. Epelbaum, J. Gegelia, U. -g. Meissner
Summary: This article applies the definition of local spatial densities using sharply localized one-particle states to spin-3/2 systems. Matrix elements of the electromagnetic current and the energy-momentum tensor are considered, and integral expressions of associated spatial distributions in terms of form factors are derived.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Particles & Fields
J. Yu. Panteleeva, E. Epelbaum, J. Gegelia, U. -G. Meissner
Summary: This paper considers the matrix elements of the electromagnetic current and energy-momentum tensor for spin-1 systems with sharply localized states. It discusses their interpretation as local spatial densities of various characteristics of the system in question.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Physics, Nuclear
A. M. Gasparyan, E. Epelbaum
Summary: We extend the renormalizability study of chiral effective field theory with a finite cutoff to nucleon-nucleon scattering, considering nonperturbative effects. The nucleon-nucleon interaction is expanded up to next-to-leading order, with the leading-order interaction treated nonperturbatively. New features related to the renormalization of the effective field theory are revealed, including more stringent constraints on the leading-order potential to ensure renormalizability and correct power counting for the next-to-leading-order amplitude. Numerical analysis of several partial waves in nucleon-nucleon scattering, 3P0, 3S1-3D1, and 1S0, is conducted to illustrate the theoretical findings, discussing cutoff dependence and convergence of the chiral expansion for these channels.
Article
Astronomy & Astrophysics
V. Baru, E. Epelbaum, A. A. Filin, C. Hanhart, A. V. Nefediev
Summary: Heavy-quark spin symmetry applies to the direct decay of heavy quarkonia, but can be overcome in the presence of multiquark intermediate states. The violation of HQSS can be balanced by the narrowness of the intermediate states, resulting in equal transition strengths into final states with different total heavy quark spins. Spin symmetry is restored when the mass of a heavy quark becomes infinite.
Article
Physics, Particles & Fields
J. Yu. Panteleeva, E. Epelbaum, J. Gegelia, U-G Meissner
Summary: Using spherically symmetric sharply localized wave packets, we determine the details of defining the spatial densities corresponding to the gravitational form factors of spin-0 and spin-1/2 systems. The expressions for the spatial densities are provided in the frames with both zero and non-zero expectation values of the momentum operator.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Nuclear
P. Yin, X. L. Shang, J. N. Hu, J. Y. Fu, E. Epelbaum, W. Zuo
Summary: We investigate the pairing properties of state-of-the-art semilocal coordinate-space and semilocal momentum-space regularized chiral interactions. We find weak regulator dependence and robust convergence in the 3SD1 and 1S0 pairing gaps, while chaotic behavior is observed for the 3PF2 results. In addition, discrepancies between the chiral interactions and the Av18 potential in the 3SD1 and 3PF2 channels suggest the need for further constraints on the nucleon-nucleon interactions in these channels at high energies. Furthermore, the different tensor force effects of the chiral interactions and the Av18 potential for the 3SD1 and 3PF2 pairing gaps indicate distinct tensor components in these interactions.
Article
Physics, Nuclear
P. Maris, R. Roth, E. Epelbaum, R. J. Furnstahl, J. Golak, K. Hebeler, T. Huether, H. Kamada, H. Krebs, H. Le, Ulf -G. Meissner, J. A. Melendez, A. Nogga, P. Reinert, R. Skibinski, J. P. Vary, H. Witala, T. Wolfgruber
Summary: This paper presents a comprehensive investigation on few-nucleon systems as well as light and medium-mass nuclei, using the current Low Energy Nuclear Physics International Collaboration two-nucleon interactions and three-nucleon forces. By considering higher-order corrections and performing correlated truncation error analysis, the resulting Hamiltonian is shown to successfully predict various observables and spectra of nucleon-deuteron scattering and light p-shell nuclei. However, the charge radii are found to be underpredicted by approximately 10% for the oxygen isotopes and almost 20% for 40Ca and 48Ca.
Article
Physics, Nuclear
J. Golak, V. Urbanevych, R. Skibinski, H. Witala, K. Topolnicki, V. Baru, A. A. Filin, E. Epelbaum, H. Kamada, A. Nogga
Summary: In this study, absorption reactions are investigated using single-nucleon and two-nucleon transition operators derived from chiral effective field theory. The results show that the absorption rates strongly depend on the nuclear pion absorption operator used and the two-body parts of the operator significantly affect the rates. The final state interactions between nucleons generated by two-nucleon forces are important, while the three-nucleon interaction plays a visible role only in certain reactions.
Article
Astronomy & Astrophysics
J. Yu. Panteleeva, E. Epelbaum, J. Gegelia, U. -G. Meissner
Summary: This paper proposes and computes a new definition of electromagnetic spatial densities for a spin-1/2 system. The results obtained are compared with the traditional definition based on the three-dimensional Fourier transforms of the electromagnetic form factors in the Breit frame.
Article
Physics, Particles & Fields
H. Alharazin, E. Epelbaum, J. Gegelia, U-G Meissner, B-D Sun
Summary: The leading one-loop corrections to the gravitational form factors of the delta resonance are calculated using chiral effective field theory. The contributions to the energy-momentum tensor and renormalization of low-energy constants are determined. Static quantities are obtained through small scale expansion, and the real and imaginary parts of the gravitational form factors are numerically calculated.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Physics, Nuclear
N. Rijneveen, A. M. Gasparyan, H. Krebs, E. Epelbaum
Summary: In this article, we study the reaction of pion photoproduction on the nucleon using chiral perturbation theory. We present results using both the covariant approach and the heavy-baryon scheme, and compare them to experimental data using Bayesian methods to estimate theoretical truncation errors. We find that the explicit treatment of the delta(1232) resonance significantly improves the description of the reaction.
Article
Physics, Nuclear
A. M. Gasparyan, E. Epelbaum
Summary: In this study, we investigate two-nucleon scattering using chiral effective field theory with a finite cutoff to next-to-leading order in the chiral expansion. We propose a scheme where the contributions of the lowest-order interaction to the scattering amplitude are summed up to an arbitrary order, while the corrections beyond leading order are iterated only once. We consider a general form of the regulator for the leading-order potential, including local and non-local structures. The main objective is to address the formal aspects of renormalizability within this scheme, and we provide a rigorous proof that power-counting breaking terms can be absorbed into the renormalization of low energy constants. We also demonstrate that the cutoff dependence of the scattering amplitude can be reduced by perturbatively subtracting the regulator artifacts at next-to-leading order. The numerical results confirm the applicability of our scheme for nucleon-nucleon scattering.
Article
Astronomy & Astrophysics
E. Epelbaum, J. Gegelia, U. -g. Meissner, M. V. Polyakov
Summary: This paper examines the low-energy chiral effective field theory of vector mesons and Goldstone bosons in an external gravitational field. It calculates the gravitational form factors and slope parameters of the p-meson, and analyzes the chiral expansion at zero momentum transfer and the long-range behavior of energy and internal force distributions.
Article
Astronomy & Astrophysics
V Baru, E. Epelbaum, A. A. Filin, C. Hanhart, A. Nefediev
Summary: An effective field theory-based coupled-channel analysis of e(+)e(-) annihilation data at BES III was performed, extracting poles responsible for the Z(cs)(3982) formation. Two scenarios were identified, providing similar mass distribution descriptions but differing predictions for the spin partners of Z(cs)(3982).
